Abstract
Adverse weather is becoming more frequent and severe due to climate change. Such events have health and economic impacts on the global population. Early warning systems exist worldwide to assess weather forecasts and alert of adverse weather. This paper presents results of a scoping evaluation and recommendations for a full evaluation of England's Weather Health Alerting system, which was completed in 2024. The work included an analysis of registered users, creating a Theory of Change, conducting stakeholder interviews and producing recommendations to support the system to achieve its long-term impact. A novel generalisable evaluation framework for public health impact-based Early Warning Systems was produced to guide this approach. This was the first evaluation since the transition to an impact-based alerting system in June 2023. Results of the user analysis highlighted that most users were part of the general public, contrary to the target audience being professionals. The Theory of Change emphasises the complex nature of the Weather Health Alerting system and demonstrates how long-term impacts can be achieved. The evaluation framework and limitations identified were used to produce a table of evaluation questions and recommendations. To conclude, we produced an evaluation framework for Early Warning Systems which would benefit from further application in other context to validate its use. In applying the framework to the Weather Health Alerting system we were able to identify what improvements could be made to achieve its long-term impact.